Description:
------------
Neither http://php.net/manual/en/class.closure.php nor 
http://www.php.net/manual/en/functions.anonymous.php mention that anonymous 
functions / lambdas bind the object they are defined in to $this, and that the 
automatic binding functionality can be avoided by declaring the lambda as 
static:

<?php
$lambda = static function() { ... }
?>

There should probably be a warning about generating lambdas in object contexts 
as it silently binds a reference to the defining object, which could cause all 
sorts headaches when attempting to cause the destruction of an object.

Defining a static lambda like the code sample above prevents the lambda from 
binding to its defining object. Please patch the documentation accordingly.

Thanks!